CN114460455A - Device and method for detecting tripping capability of electromagnetic tripping device of low-voltage direct-current circuit breaker - Google Patents
Device and method for detecting tripping capability of electromagnetic tripping device of low-voltage direct-current circuit breaker Download PDFInfo
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Abstract
A device and a method for detecting the tripping capability of an electromagnetic tripping device of a low-voltage direct-current circuit breaker belong to the field of detection devices, and aim at directly acquiring the magnetic field intensity of the tripping action of the circuit breaker by an analog Hall sensor without disassembling the circuit breaker device, calculating the electromagnetic attraction of a tripping coil, thereby realizing the purpose that the Hall sensor is used for detecting whether the electromagnetic attraction of the tripping coil of the low-voltage direct-current circuit breaker reaches a tripping condition, detecting whether the low-voltage direct-current circuit breaker completes the function of controlling the on-off of current and timely informing a transport inspection person of the detection result, and the device comprises an analog Hall sensor unit, a signal detection processing unit, a circuit on-off state indicating unit and a 4G communication unit, comparing the parameters of the detection result, judging whether the detection result is normal or not, detecting in real time and informing the relevant transport inspection person of the detection result, has the advantages of simple structure, easy operation and low manufacturing cost.
Description
Technical Field
The invention relates to the field of detection devices, in particular to a device and a method for detecting the tripping capability of an electromagnetic tripping device of a low-voltage direct-current circuit breaker.
Background
Compared with alternating current power distribution, direct current power distribution has the advantages of large transmission capacity, high power supply reliability, good power quality and the like, and the direct current power distribution technology is adopted in the fields of aerospace, ships, rail transit and the like at present. The low-voltage direct-current circuit breaker is widely used as electrical equipment in a low-voltage distribution system, plays a role in controlling a sectionally closed system in a power grid and a role in protecting the safe and reliable operation of the power grid, and can cause power grid accidents or enlarge accidents when the low-voltage direct-current circuit breaker breaks down, so that direct economic loss is caused.
The low-voltage direct-current circuit breaker mainly comprises a release, an arc extinguishing system, a transmission mechanism, a base frame, a shell and the like, wherein the release is one of key parts of the circuit breaker. The magnetic tripping device is one of tripping devices, the working principle of the magnetic tripping device is based on the electromagnetic principle, an electromagnet excited by main circuit current in series is relied on, when fault current reaches a setting value, a movable iron core in the electromagnet moves towards the direction that an air gap is reduced under the action of a magnetic field, and meanwhile, a tripping device is driven to enable a mechanism to be switched off by overcoming the counter force of a spring. Some circuit breakers often operate under abnormal conditions such as overvoltage, overload, short circuit, etc., and the operating state of the release directly determines the protection characteristics of the circuit breaker.
At present, relevant research in China is basically focused on a high-voltage circuit breaker, so that a method and a device for detecting the safety state of a release of a low-voltage direct-current circuit breaker on a power distribution side are needed, and the safety state diagnosis of the low-voltage direct-current circuit breaker is realized.
The traditional safety inspection method for the circuit breaker in China is to carry out regular maintenance, needs to disassemble equipment, is high in blindness and cost, is easy to damage the circuit breaker after disassembly and assembly, and reduces the utilization rate and reliability. At present, China develops a new maintenance mode, namely, condition maintenance, equipment in operation is subjected to safety assessment or diagnosis through various methods, and then corresponding measures are taken pertinently to ensure reliable operation of the equipment, but related research is basically focused on detection and diagnosis of a high-voltage circuit breaker, and research on low-voltage direct-current circuit breakers is shallow.
A test platform body with complete functionality is required. The test cycle is long, because the test range is wide, the range that needs the outage to dismantle is just wide, and the influence scope is big.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a device and a method for detecting the tripping capability of an electromagnetic tripping device of a low-voltage direct-current circuit breaker, which can solve the problems that the electromagnetic attraction of a tripping coil can be calculated by directly acquiring the magnetic field intensity of the tripping action of the circuit breaker through an analog Hall sensor without disassembling the circuit breaker device, so that whether the electromagnetic attraction of the tripping coil of the tripping device of the low-voltage direct-current circuit breaker reaches a tripping condition or not is detected by the Hall sensor, whether the low-voltage direct-current circuit breaker completes the function of controlling the on-off of current or not is detected, and a detection result is timely notified to a transportation and inspection person.
The first technical scheme adopted by the invention is as follows:
the tripping capability detection device of the electromagnetic tripping device of the low-voltage direct-current circuit breaker comprises an analog Hall sensor unit, a signal detection processing unit, a circuit on-off state indicating unit and a communication unit;
the analog Hall sensor unit is connected with the signal detection processing unit, and the line on-off state indicating unit and the communication unit are respectively connected with the signal detection processing unit;
the analog Hall sensor unit is used for acquiring electromagnetic attraction forming signals of a tripping coil of a low-voltage direct-current circuit breaker;
the signal detection processing unit is used for processing and logically judging the signal;
the circuit on-off state indicating unit is used for indicating the on-off state of the circuit;
and the communication unit is used for transmitting information to the operation and inspection personnel.
Further, the communication unit is a 4G communication unit for information transmission using 4G signals.
Furthermore, the signal detection processing unit comprises an operational amplifier circuit and a microprocessor unit, wherein the microprocessor unit comprises an A/D conversion interface and an I2The interface C and the UART interface;
the output end of the analog Hall sensor unit is connected with the operational amplification circuit, the output end of the operational amplification circuit is connected with the A/D conversion interface of the microprocessor unit, the UART interface of the microprocessor unit is bidirectionally connected with the 4G communication unit, and the circuit on-off state indicating unit is connected with the I of the microprocessor unit2C, interface connection;
the operational amplifier circuit is used for amplifying the signal;
and the microprocessor unit is used for finishing the operation processing of the data after the A/D conversion.
Furthermore, the circuit on-off state indicating unit comprises a photosensitive device, a circuit on-off state indicating lamp and a current limiting resistor;
one end of the current-limiting resistor is connected with one end of the circuit on-off state indicator light, the other ends of the circuit on-off state indicator light and the current-limiting resistor are connected with the power supply, light of the circuit on-off state indicator light is transmitted to the photosensitive device, and the output end of the photosensitive device is connected with the I of the microprocessor unit2C, interface connection;
the circuit on-off state indicator lamp is used for providing a light source for the photosensitive device;
the current limiting resistor is used for limiting the current of the branch circuit to prevent the component connected in series from being burnt out due to overlarge current;
and the photosensitive device is used for detecting illumination and outputting a detection result to the microprocessor unit.
Furthermore, the model of the analog Hall sensor unit is SS495, and the working temperature range is as wide as-40-150 ℃.
Further, the microprocessor unit is of the model STM32F103RBT 6.
Further, the operational amplifier is of a model LM 358.
Further, the model of the photosensitive device is BH 1750.
The second technical scheme adopted by the invention is as follows:
the method for detecting the tripping capacity of the electromagnetic tripping device of the low-voltage direct-current circuit breaker is realized according to any one of the devices, and comprises the following steps:
step S1, collecting the electromagnetic attraction of a tripping coil of a tripping device of the low-voltage direct-current circuit breaker through an analog Hall sensor unit;
step S2, the output voltage analog signal is amplified by the operational amplifier circuit, and the analog signal processed by the amplifier circuit enters the microprocessor;
step S3, comparing the parameters of the detection result and judging whether the parameters are normal or not;
and step S4, when current capable of triggering the release acts on the circuit, the release acts to push the breaker to act to break the power transmission line, so that the on-off state indicator of the circuit is turned off, the photosensitive device cannot detect light, a detection result is output to the microprocessor unit, and the microprocessor unit judges whether the breaker is broken by the signal.
Further, in step S3, the implementation process of comparing the parameters of the detection result and determining whether the detection result is normal is as follows:
obtaining the AD value U of the voltage through the A/D conversion interface of the microprocessor unitadAccording to UadObtaining an output voltage value UoutFormula (ii)The following were used:
in the formula (1), a is a coefficient calculated according to the relation between the reference voltage of the AD converter and decimal and binary, and n is an n-bit AD converter;
according to UoutCalculating a magnetic induction intensity value B, wherein the formula is as follows:
according to the magnetic induction intensity value B, calculating the electromagnetic attraction force F, wherein the formula is as follows:
in the formula (3), u0Is air permeability, u0＝1.25×10-6(H/m), A is the magnetic pole area (m)2)；
The obtained voltage value U is measuredoutAnd comparing the magnetic induction intensity value B and the electromagnetic attraction force F data with set initial values to judge whether the abnormity occurs.
The invention has the beneficial effects that:
1. the device can detect in real time, informs relevant operation personnel of the detection result, and has the advantages of simple structure, easy operation and low manufacturing cost.
2. A corresponding scheme is provided for the detection of the low-voltage direct-current circuit breaker.
3. Convenient operation need not to dismantle the circuit breaker device, can directly acquire the magnetic field intensity when the circuit breaker opens and shuts the floodgate action through analog type hall sensor, and calculate the electromagnetic attraction of trip coil, thereby realize detecting whether low-voltage direct current circuit breaker tripper trip coil electromagnetic attraction reaches the dropout condition with hall sensor, and detect whether low-voltage direct current circuit breaker has accomplished the function of control current break-make, can in time inform fortune inspector detection result, have obvious help to accurately detecting circuit breaker dropout ability.
4. The testing device described in the embodiment can be used for detecting the suspected contactor at any time, has high testing efficiency, short power-off time and small influence range, and can quickly restore power supply under the condition of no fault.
5. Easy training is used, and follow-up maintenance dismantles conveniently, and the hardware all is the general product on the market, replaces easy maintenance.
6. The system has low power consumption, is energy-saving and environment-friendly, and reduces the economic cost of use.
Drawings
Fig. 1 is a block diagram of a tripping capability detection device of an electromagnetic trip of a low-voltage dc circuit breaker according to the present application;
fig. 2 is a flowchart of a tripping capability detection method of an electromagnetic trip of a low-voltage dc circuit breaker according to the present application.
Detailed Description
The first embodiment is as follows:
as shown in fig. 1, the device for detecting the tripping capability of the electromagnetic trip of the low-voltage direct-current circuit breaker comprises an analog hall sensor unit, a signal detection processing unit, a circuit on-off state indicating unit and a 4G communication unit. The signal detection processing unit comprises an operational amplifier circuit and a microprocessor unit, wherein the microprocessor unit comprises an A/D conversion interface and an I2The circuit on-off state indicating unit comprises a photosensitive device, a circuit on-off state indicating lamp and a current-limiting resistor.
The analog Hall sensor unit is connected with the signal detection processing unit, and the line on-off state indicating unit and the 4G communication unit are respectively connected with the signal detection processing unit;
the output end of the analog Hall sensor unit is connected with an operational amplifier circuit, the output end of the operational amplifier circuit is connected with an A/D conversion interface of a microprocessor unit, and a UART interface of the microprocessor unit is bidirectionally connected with a 4G communication unit;
one end of the current-limiting resistor is connected with one end of the circuit on-off state indicator light, the other ends of the circuit on-off state indicator light and the current-limiting resistor are connected with the power supply, light of the circuit on-off state indicator light is transmitted to the photosensitive device, and the output end of the photosensitive device is connected with the I of the microprocessor unit2C, interface connection;
the second embodiment is as follows:
the analog Hall sensor unit is used for acquiring electromagnetic attraction of a tripping coil of a low-voltage direct-current circuit breaker to form a signal, the output voltage analog signal is amplified by the operational amplifier circuit, the analog signal processed by the operational amplifier circuit enters the microprocessor unit through an A/D conversion interface of the microprocessor unit, and the microprocessor unit processes the analog signal to obtain an AD value U of voltagead。
The method for detecting the tripping capability of the electromagnetic tripping device of the low-voltage direct-current circuit breaker compares parameters of a detection result and judges whether the detection result is normal or not.
According to UadObtaining an output voltage value UoutThe formula is as follows:
in the formula (1), a is a coefficient calculated according to the relation between the reference voltage of the AD converter and decimal and binary, and n is an n-bit AD converter;
according to UoutCalculating a magnetic induction intensity value B, wherein the formula is as follows:
according to the magnetic induction intensity value B, calculating the electromagnetic attraction force F, wherein the formula is as follows:
in the formula (3), u0For air permeabilityRate, u0＝1.25×10-6(H/m), A is the magnetic pole area (m)2)；
The obtained voltage value U is measuredoutAnd comparing the magnetic induction intensity value B and the electromagnetic attraction force F data with set initial values to judge whether the abnormity occurs.
In the circuit on-off state indicating unit, the indicating lamp and the photosensitive device are hermetically packaged, so that the influence of environmental illumination is avoided. The indicating lamp gets electricity from the circuit breaker lower port, and the series has the current limiting resistance, when the electric current that can trigger the release action appears in the circuit, because the release action promotes the circuit breaker action and breaks off transmission line, the indicating lamp goes out. Photosensitive device pass through I2The C interface is connected with the microprocessor unit. When the release pushes the circuit breaker to cut off the line power supply, the photosensitive device cannot detect the illumination, the detection result is output to the microprocessor unit, and the microprocessor unit judges whether the circuit breaker is cut off or not according to the signal.
Data information of the detection result is sent to a mobile phone APP of the operation and inspection personnel through the 4G communication unit, and the operation and inspection personnel can be timely notified through short messages and the like.
The analog Hall sensor is a linear Hall sensor with the model of SS495, is small in size and convenient to install and use, and the output voltage is in a linear relation with the change of the magnetic field intensity, so that the measured value is convenient to calculate. The built-in functional circuit does not need to be matched with an external filter circuit, the built-in thin film resistor enhances the temperature stability and the output precision of the device, the working temperature range is as wide as minus 40 ℃ to 150 ℃, and the circuit is suitable for most circuit breakers; the operational amplifier is LM 358; the type of the microprocessor unit is STM32F103RBT 6; the model of the photosensitive device is BH 1750.
It should be noted that, in the above embodiments, as long as the technical solutions can be aligned and combined without contradiction, those skilled in the art can exhaust all possibilities according to the mathematical knowledge of the alignment and combination, and therefore, the present invention does not describe the technical solutions after alignment and combination one by one, but it should be understood that the technical solutions after alignment and combination have been disclosed by the present invention.
This embodiment is only illustrative of the patent and does not limit the scope of protection thereof, and those skilled in the art can make modifications to its part without departing from the spirit of the patent.
Claims (10)
1. The device for detecting the tripping capability of the electromagnetic trip of the low-voltage direct-current circuit breaker is characterized by comprising an analog Hall sensor unit, a signal detection processing unit, a circuit on-off state indicating unit and a communication unit;
the analog Hall sensor unit is connected with the signal detection processing unit, and the line on-off state indicating unit and the communication unit are respectively connected with the signal detection processing unit;
the analog Hall sensor unit is used for acquiring electromagnetic attraction forming signals of a tripping coil of a low-voltage direct-current circuit breaker;
the signal detection processing unit is used for processing and logically judging the signal;
the circuit on-off state indicating unit is used for indicating the on-off state of the circuit;
and the communication unit is used for transmitting information to the operation and inspection personnel.
2. The apparatus of claim 1, wherein the communication unit is a 4G communication unit for information transmission using a 4G signal.
3. The apparatus for detecting the tripping capability of the electromagnetic trip of the low-voltage dc circuit breaker according to claim 2, wherein the signal detection processing unit comprises an operational amplifier circuit and a microprocessor unit, and the microprocessor unit comprises an a/D conversion interface, an I/D conversion interface2The interface C and the UART interface;
the output end of the analog Hall sensor unit is connected with the operational amplifier circuit, the output end of the operational amplifier circuit is connected with the A/D conversion interface of the microprocessor unit, the UART interface of the microprocessor unit is bidirectionally connected with the 4G communication unit, and the circuitOn-off state indicating unit and I of microprocessor unit2C, interface connection;
the operational amplifier circuit is used for amplifying the signal;
and the microprocessor unit is used for finishing the operation processing of the data after the A/D conversion.
4. The apparatus for detecting the tripping capability of the electromagnetic trip of the low-voltage direct current circuit breaker according to claim 3, wherein the line on-off state indicating unit comprises a photosensitive device, a line on-off state indicating lamp and a current limiting resistor;
one end of the current-limiting resistor is connected with one end of the circuit on-off state indicator light, the other ends of the circuit on-off state indicator light and the current-limiting resistor are connected with the power supply, light of the circuit on-off state indicator light is transmitted to the photosensitive device, and the output end of the photosensitive device is connected with the I of the microprocessor unit2C, interface connection;
the circuit on-off state indicator lamp is used for providing a light source for the photosensitive device;
the current limiting resistor is used for limiting the current of the branch circuit to prevent the component connected in series from being burnt out due to overlarge current;
and the photosensitive device is used for detecting illumination and outputting a detection result to the microprocessor unit.
5. The apparatus for detecting the tripping capability of the electromagnetic trip of the low-voltage direct-current circuit breaker according to claim 4, wherein the model of the analog Hall sensor unit is SS495, and the operating temperature range is as wide as-40 ℃ to 150 ℃.
6. The apparatus for detecting the tripping capability of an electromagnetic trip of a low-voltage direct current circuit breaker according to claim 5, wherein said microprocessor unit is of the type STM32F103RBT 6.
7. The apparatus as claimed in claim 6, wherein the operational amplifier is LM 358.
8. The apparatus for detecting the tripping capability of the electromagnetic trip of the low-voltage direct-current circuit breaker according to claim 7, wherein the model of the photosensitive device is BH 1750.
9. Method for detecting the tripping capability of an electromagnetic trip of a low-voltage direct-current circuit breaker, realized according to the device of any one of claims 1 to 8, characterized in that it comprises the following steps:
step S1, collecting the electromagnetic attraction of a tripping coil of a tripping device of the low-voltage direct-current circuit breaker through an analog Hall sensor unit;
step S2, the output voltage analog signal is amplified by the operational amplifier circuit, and the analog signal processed by the amplifier circuit enters the microprocessor;
step S3, comparing the parameters of the detection result and judging whether the parameters are normal or not;
and step S4, when current capable of triggering the release acts on the circuit, the release acts to push the breaker to act to break the power transmission line, so that the on-off state indicator of the circuit is turned off, the photosensitive device cannot detect light, a detection result is output to the microprocessor unit, and the microprocessor unit judges whether the breaker is broken by the signal.
10. The method for detecting the tripping capability of the electromagnetic trip of the low-voltage direct-current circuit breaker according to claim 9, wherein the step S3 is implemented by comparing parameters of the detection result and determining whether the parameters are normal as follows:
obtaining the AD value U of the voltage through the A/D conversion interface of the microprocessor unitadAccording to UadObtaining an output voltage value UoutThe formula is as follows:
in the formula (1), a is a coefficient calculated according to the relation between the reference voltage of the AD converter and decimal and binary, and n is an n-bit AD converter;
according to UoutCalculating a magnetic induction intensity value B, wherein the formula is as follows:
according to the magnetic induction intensity value B, calculating the electromagnetic attraction force F, wherein the formula is as follows:
in the formula (3), u0Is air permeability, u0＝1.25×10-6(H/m), A is the magnetic pole area (m)2)；
The obtained voltage value U is measuredoutAnd comparing the magnetic induction intensity value B and the electromagnetic attraction force F data with set initial values to judge whether the abnormity occurs.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116430134A (en) * | 2023-03-08 | 2023-07-14 | 上海正泰智能科技有限公司 | Undervoltage release detection method, detection device and storage medium |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116430134A (en) * | 2023-03-08 | 2023-07-14 | 上海正泰智能科技有限公司 | Undervoltage release detection method, detection device and storage medium |
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